Flow and Sediment Movement Characteristics on the Varisized Plain

of Compound Channel

Zuwen Ji

, Dangwei Wang, Qing Lu and Anjun Deng

State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and

Hydropower Research (IWHR), 20 Chegongzhuang West Road, Beijing, 100048, China

Keywords:

Compound channel, Flow velocity, Sediment concentration, Main channel, Flood plain

Abstract: In this paper, river reaches are generalized into two types: the straight and lotus-root-shape compound

channels according to plane characters of the Lower Yellow River and the Songhuajiang River. It can be seen

from some experimental data of flow and sediment in two kinds of channels. The difference arises from the

fact that the momentum transfer is stronger in the louts-root-shape channel than in the straight channel. Thus,

the relative velocity of plain to channel type, still increases with increment of the relative depth, their

differences are large at the lower relative depth, but close at the higher one. The distributions of flow velocities

in two channels are similar with water depth, and the mean velocities are on the decline from main channel to

flood plain. At two sides of floodplain, the change ranges from maximal to minimal velocities. Transverse

velocity gradient in the interface area is bigger in the straight channel than in the lotus-root-shape channel.

This is largely because, relative sediment concentration in both compound channels go up with the increase

of the relative velocity and depth. The relationship of sediment concentration to depth, is such that, the

enlarging speed is more rapid in the straight channel than in the lotus-root-shape channel. The transverse

variation of the vertical average sediment concentration is smaller in the lotus-root-shape channel than in the

straight channel, and are bigger on the plain than in the channel.

1 INTRODUCTION

The average annual sediment load in the Lower

Yellow River was 1.6 billion tons before 1980s, and

ranked first in the world. The average sediment

concentration was 35 kg/m

and the highest sediment

concentration was recorded at 911 kg/m

. Large

quantities of sedimentation have resulted in

“suspended rivers” and frequent shift of the river

courses in the lower reaches. The average level of

riverbed is 4 to 6 m higher than that of normal ground

level, and the maximum has reached 13m in some

places. This explains why Throughout the history of

China, the Yellow River has been associated with

floods and famine. It has been a difficult problem to

harness the Yellow River because, the whole length

of the lower reach is about 878 kilometers. In its plane

form, it is involved in mainly meandering and

wandering, and their configurations of cross-section

include two parts: main channel and floodplain. The

area of floodplain is about 3,544 km

, accounting for

84 % in the total area of the river. Thus, it is very

important to study flow and sediment in the

compound channel in the Lower Yellow River.

Compound channels are universal forms of fluvial

river, and are often in areas that are densely populated

and economically developed. Compound channels

are different in form of expression from those in the

natural rivers. From the point of view of cross-

sectional shape, although all compound channels

have basic forms like main channel and flood plain,

other variants exist such as, one plain with one

channel, two plains with one channel, and even much

more channels and plains; For plane form, there are

equally many expressions, such as straight channel,

lotus-root-shape channel, meandering channel and so

on, increasing the complexity of the research. The

problems that overbank flooding of compound

channels causes necessitates water resource planning,

floodplain planning, flood level design, channel

improvement and so on. At present, the research on

the overbank flow in the compound channels mainly

focuses on the study of the flow structure and the

interaction mechanism of the plain channel. The bed

shear stress and resistance characteristics of the

Ji, Z., Wang, D., Lu, Q. and Deng, A.

Flow and Sediment Movement Characteristics on the Varisized Plain of Compound Channel.

In Proceedings of the 7th International Conference on Water Resource and Environment (WRE 2021), pages 171-178

ISBN: 978-989-758-560-9; ISSN: 1755-1315

 2022 by SCITEPRESS – Science and Technology Publications, Lda. All r ights reserved

171

compound channel were also observed (Lyhess et al.,

2001; Knight, 1999). The relationship between flow

structure and flow distribution characteristics and bed

morphology were studied (Hu et al., 2010;

Wormleaton et al., 2004; Ji et al., 2016). The basic

exchange model and distribution characteristics of

flow and sediment were put forward (Armugha et al.,

2018; Chen & Zhang, 1996; Knight, 2005; Moron et

al., 2017). The influence of overland flow on bed

morphology, surface slope and sediment transport

were analysed (Tang & Knight, 2006; Ji et al., 2019;

Wu et al., 2020). The above results lay a good

foundation for related researches of compound

channel, as presented by the analysis of two

generalization physical model experiments.

2 EXPERIMENTAL

METHODOLOGY

This experimental study conducted on a 30m long

circulating straight channel, with basic dimensions of

width of 0.3m, floodplain width of 0.7m and beach

channel bed height difference of 0.06m. The bed

surface and side wall of water channel are both

cement surfaces, and the water channel structure is

shown in Figure 1 (a) to (c). For lotus-root-shape

channels, the width of main channel was 0.3m and the

width of floodplain was 0-0.7m. The whole water

channel is composed of four lotus roots with each

having a length of 4m. The transition section with the

length of 1m exists between every two lotus roots.

The outer boundary of each lotus root is symmetrical

about the axis of the main channel circular arc and

curvature of 0.17m. The water channel structure is

indicated in Figure 1(b) and Figure 1 (c), and 7 cross

sections are arranged on experimental measurement

section.

In this experiment, cross-sections of straight

channel and lotus-root-shape channel are both

considered, rectangles with equal main channel width

and beach channel height difference. However, the

outer boundary of straight channel is unchanged

along the way, and that of lotus-root-shape channel is

curved with a great change along the way. In order to

facilitate comparison, the lotus-root-shape channels

adopt 4

cross section, and the size of this section is

exactly consistent with that of straight channel.

During the experiment, the experimental water depth

of straight compound channel is taken as 0.02 m~

0.13m, and the sediment concentration is 4 ~

83kg/m

; the experimental water depth of lotus-root-

shape compound channel is given by 0.07 ~ 0.12 m,

while the sediment concentration is 4 ~ 25kg/m

Both compound channels use the same experimental

sand with a median grain size of 0.014mm.

Figure 1: Sketches of the straight and the lotus-root-shape compound channels.

3 COMPARATIVE ANALYSIS ON

FLOW MOVEMENT

CHARACTERISTICS OF TWO

TYPES OF COMPOUND

CHANNELS

3.1 Cross-section Flow Capability

According to the water level flow relationship

between straight channel and lotus-root-shape

channel, it can be known that under the same water

depth, whether for main channel or floodplain, the

flow capacity of lotus-root-shape channel is less than

that of straight channel. The greatest difference lies in

total flow capacity of cross section, closely followed

by the flow capacity of main channel, relative to the

smallest difference in the flow capacity of floodplain.

In case of small water depth of floodplain, the

difference in the flow capacity of the two channels is

small. As the water depth increases, that difference

becomes gradually greater.

Figure 2 shows the water level flow relationship

between three channels, i.e., single channel, straight

compound channel and lotus-root-shape compound

WRE 2021 - The International Conference on Water Resource and Environment

172

channel. Among them, the water level flow

relationship of straight channel and lotus-root-shape

channel are measured from data acquired by the

author, while that of single channel is the calculation

result obtained from the Manning formula assuming

the water depth to flow area is same as straight

channel to lotus-root-shape channel. It can be seen

from the figure that under the same water depth and

flow area, the single channel has the largest flow

capacity, followed by straight channel, and the least

is lotus-root-shape channel. Meanwhile, the

difference in the flow capacity of the three channels

becomes greater with water depth. In the case where

the relative water depth of floodplain is about 0.14 ~

0.51, the flow capacity of straight channel is reduced

by 7% - 21% compared with single channel; the flow

capacity of lotus-root-shape channel is reduced by

11% - 48% over single channel; the flow capacity of

lotus-root-shape channels is reduced by 4% - 34%

over straight channel.

Figure 2: Stage-discharge relations in single.

3.2 Average Flow Velocity of

Floodplain

The change in average flow velocity of lotus-root-

shape channel floodplain is basically like that of

straight channel. The flow velocity of main channel

and cross section increases first and then decreases

and then increases again with water depth. However,

the flow velocity of floodplain indicates monotonic

increases with water depth. The characteristics of this

change show that there is momentum exchange

between the floodplains of the two channels, but the

intensity is different, as shown in Figure 3. It can be

seen from the figure that regardless of water depth on

floodplain, the flow velocity of lotus-root-shape

channel is larger than that of straight channel. This

shows laterally, momentum exchange between the

lotus-root-shape channels is stronger than that of the

straight channel. Because the outer boundary of the

straight channel is straight, the longitudinal change of

floodplain flow is not large. In the lateral direction,

there is a certain difference in the flow velocity of

floodplain, which is small for lotus-root-shape

channels. This is because in the straight channel, the

floodplain current itself has a certain momentum. If

there is no floodplain momentum exchange, the

floodplain current cannot also flow.

Figure 3: Relations between relative velocity and straight

and lotus root - shape channels relative depth corresponding

to plain and channel.

This momentum is provided by the gravity

component of uniform water flow. The reason for the

momentum exchange between the floodplains is

mainly due to the certain difference in the flow

velocity of the two channels, and such difference

gradually decreases over water depth. However, in

the lotus-root-shape channels, the floodplain water

movement is different. Running in the transition

section, because of the single channel, the flow speed

is high. When the flow enters the diffusion section,

the current with higher momentum is transmitted to

floodplain. While before the momentum exchange of

floodplain current is very small. On the one hand, the

flow velocity of floodplain is very small; balanced on

the other hand, by the high velocity flow just before

entering the diffusion section. It is conceivable that

when they meet, due to the large difference in

velocity between the two channels, violent

momentum exchange will inevitably occur.

Therefore, the floodplain momentum exchange of

lotus-root-shape channels is stronger than that of

straight channels.

In addition, it can be seen from Figure 3 that when

the relative water depth of floodplain is relatively

small, the difference in the floodplain velocity of the

two channels is large. In case of larger water depth of

floodplain, the floodplain velocity ratio of the two

channels has a small effect.

Flow and Sediment Movement Characteristics on the Varisized Plain of Compound Channel

173

For a certain flowing cross-section, the momentum

of the water body on cross-section is constant. The

momentum of floodplain will increase, and the

momentum of main channel will be reduced. The

momentum exchange of lotus-root-shape channel

floodplain is more intense than that of the straight

channel. The momentum transferred from former

main channel to floodplain will be large inevitably, so

that the momentum of the main channel on lotus-root-

shape channels decreases more, and the increase in

amplitude of the momentum on floodplain is

relatively larger. Therefore, the floodplain velocity

ratio of lotus-root-shape channel is larger than that of

the straight channel. When the water depth of

floodplain is small, due to the larger floodplain

resistance, a considerable part of the reduced

momentum of the main channel is used to overcome

the floodplain resistance, and the actual momentum

obtained on the floodplain decreases. In the case of

basically equal water depths of the two channels, the

reduced momentum of main channel on lotus-root-

shape channel is larger than that of the straight

channel. It is shown that on the one hand, the main

channel of the lotus-root-shape channel reduces the

momentum more, and the floodplain indicates more

increased momentum; On the other hand, when the

momentum of the main channel of the straight

channel is reduced, the momentum of floodplain is

also less increased. Among the reduced momentum

of the main channel of the straight channel, the

momentum used to increase the velocity of floodplain

is less weighted relative to the remaining momentum

of the main channel. However, in the reduced

momentum of the main channel in the lotus-root-

shape channels, the momentum used to increase the

flow velocity of floodplain has a greater weight in the

remaining momentum of the main channel. When the

water depth of floodplain is relatively small, the

weight of the two channel types differs greatly, which

is expressed in the flow velocity ratio of floodplain,

i.e., the difference in floodplain velocity of lotus-root-

shape channels is greater than that of the straight

channel. With the increase of water depth on

floodplain, the difference in weight between the two

channels gradually decreases, and the difference in

floodplain velocity ratio also gradually decreases.

3.3 Vertical Velocity

There are some differences between the vertical

velocity distribution of lotus-root-shape compound

channel and the straight channel, which is mainly

manifested near the interface of floodplain. The

vertical velocity distribution of the straight channel is

large in the middle and small at two ends, while that

of lotus-root-shape channel basically shows the

characteristics of larger on the top while small at the

bottom, but the distribution is relatively uniform.

According to preliminary analysis, the momentum

exchange of floodplain in the straight channel is only

concentrated in a certain depth below the water

surface, which reaches the maximum at the water

surface and gradually weakens downward. This

exchange method determines that the vertical velocity

distribution is large in the middle, while small on

surface and bottom. However, in the lotus-root-shape

channels, almost the entire vertical line from water

surface to the bottom participates in the floodplain

momentum exchange, which is mainly due to the

strong momentum exchange of floodplain in lotus-

root-shape channels. The momentum exchange

process ensures that the main water body channel

with larger momentum entrains the floodplain water

body with less momentum into the main channel

water body. In addition, the main water body channel

with larger momentum in equivalent volume enters

the floodplain water body, which leads to the increase

of floodplain water body momentum. According to

the principle of conservation of momentum, it can be

shown that the momentum of main channel water

body will decrease. Due to the large difference in the

flow velocity of floodplain water body (especially

when it starts to diffuse), for the entrainment of main

water body channel on floodplain water body, almost

the entire vertical water body above the floodplain

bed surface participates in such exchange. It can be

seen from the rapid increase of floodplain flow

velocity that such exchange of massive water body

causes a sharp decrease in the momentum of the upper

water body of the main channel. The momentum

difference between the lower and upper water bodies

of the main channel becomes large sharply, so that the

upper and lower water bodies will inevitably generate

momentum exchange. This results in most of the

water bodies on the vertical line of the main channel

participating in the momentum exchange. The result

of this momentum exchange is the redistribution of

the momentum throughout the entire vertical line of

the main channel. In the vertical distribution, the

velocity is relatively uniform with small gradient, and

the distribution still shows the characteristics of larger

on the top and lower at the bottom, but the velocity

value of the entire vertical line decreases. It should be

noted that although there is also momentum exchange

in the vertical direction of water body of the straight

channel, the momentum exchange in the floodplain is

smaller than lotus-root-shape channel. Meanwhile,

momentum exchange is also gradual in the vertical

WRE 2021 - The International Conference on Water Resource and Environment

174

direction, i.e., gradually increasing from the

momentum exchange occurrence area to water

surface, and there is no sharp change between the

upper and lower water bodies in the area where the

momentum exchange occurs.

3.4 Average Velocity of Vertical Line

Distributed along the Lateral

Direction

The vertical average velocity of lotus-root-shape

compound channel is basically similar to that of the

straight channel in the lateral distribution. The

vertical average velocity gradually decreases from the

central area of the main channel to both sides of the

floodplain, as shown in Figure 4. However, there are

some differences between the two channels. First, the

difference between the maximum and minimum

velocity of the floodplain is different. The variation in

flow velocity of the lotus-root-shape channel is

smaller than that of the straight channel. Secondly,

the decreasing rate of vertical average velocity of

lotus-root-shape channel is smaller than that of the

straight channel. Lastly, the vertical average velocity

of the two kinds of compound channels differs greatly

in the main channel, while less in the floodplain.

Figure 4: Transverse distributions of the depth - averaged

velocity.

From the previous analysis, it can be known that

the movement status of floodplain flow of the lotus-

root-shape and straight channels before momentum

exchange of floodplain is different. For the main

channel, on the one hand, the difference in the flow

capacity of the two channels determines whether the

main channel of lotus-root-shape channel has less

momentum than the straight channel. On the other

hand, the momentum exchange of main channel flow

of the lotus-root-shape channel has larger weight than

the straight channel. Determined by the combined

effect of these two aspects, the vertical average

velocity of the main channel of the lotus-root-shape

channel is relatively smaller than that of the straight

channel. For the floodplain, on the one hand, the

momentum of the main channel water body in the

lotus-root-shape channel used for the momentum

exchange of floodplain has a larger weight. The unit

water body on the floodplain of the lotus-root-shape

channel gains more momentum than the straight

channel. On the other hand, before momentum

exchange, the floodplain water body of the straight

channel already has a certain momentum, while the

momentum of floodplain flow of the lotus-root-shape

channel is very small. Therefore, the combined effect

of these two aspects determines that the flow velocity

of the floodplain of the straight channel is larger than

the lotus-root-shape channel, but the difference

between the two channels is relatively smaller than

that of the main channel.

Figure 5: Relations among sediment concentration

corresponding to main channel, floodplain and cross section.

Flow and Sediment Movement Characteristics on the Varisized Plain of Compound Channel

175

4 COMPARATIVE ANALYSIS ON

SEDIMENT CONCENTRATION

DISTRIBUTION

CHARACTERISTICS OF TWO

TYPES OF COMPOUND

CHANNELS

4.1 Average Sediment Concentration of

Floodplain

The distribution of the average sediment

concentration in the floodplain of the lotus-root-shape

compound channel has certain similarities to that of

the straight channel. In general, the average sediment

concentration of floodplain is less than that of the

main channel. However, the average sediment

concentration ratio of the floodplain cross section of

lotus-root-shape channels varies contrarily with the

change of the sediment inflow and the straightness of

the channel. As shown in Figure 5, the reason for this

difference may be due to the different boundary

characteristics of the two channels.

In the straight channel, the boundary is straight,

the flow of floodplain and main channel has a certain

capacity, and the momentum exchange occurs due to

the different velocity of the two channels. Because the

boundary is constant along the way, when the water

body runs a distance, the water body between

floodplain will reach a dynamic balance, the same is

true of the movement of sediment in the water body

of floodplain. In the straight channel, the water body

of floodplain has a certain ability to independently

carry sediment. Although the sediment in the water

body of main channel will enter floodplain partially

through the momentum exchange of floodplain, the

sediment of floodplain also enters the main channel

through the exchanges of water body. The average

sediment concentration of floodplain is less than that

of the main channel thus, the net transport of sediment

in the main channel to floodplain occurs. Before the

sediment concentration in the water body of

floodplain reaches saturation, the average sediment

concentration of floodplain is relatively small.

Therefore, the sediment transported to floodplain

from main channel is smaller compared to the

sediment carried by the floodplain itself, which is

negligible. In this case, since there is no obvious

siltation in the water body of floodplain, the average

sediment concentration of the floodplain changes

little. Therefore, the ratio of the average sediment

concentration of floodplain to the average sediment

concentration of cross section changes little with

sediment inflow. After the average sediment

concentration of floodplain reaches saturation, as

sediment inflow increases, the average sediment

concentration of the main channel also rises, but that

of floodplain cannot reach a significant increase due

to saturation. Therefore, the ratio of average sediment

concentration of floodplain to the average sediment

concentration of cross section (reflecting sediment

inflow) decreases as sediment inflow increases, and

the ratio of average sediment concentration of the

main channel to that of cross section increases as

sediment inflow increases. As the sediment inflow

increases, the siltation on floodplain increases, and

the net sediment transported to the floodplain from

the main channel increases. This also suppresses the

increase in the average sediment concentration of the

main channel and cross section to a certain extent. In

the lotus-root-shape channels, the channel boundary

is curved, and the flow cross-section of floodplain

varies greatly. The boundary characteristics of the

lotus-root-shape compound channel determine that

the momentum required for the movement of

floodplain is mainly provided by water body of main

channel. Similarly, the sediment carried by water

body of floodplain is also provided by the sediment

in the water body of the main channel. This means

that with the exchange of water body of floodplain

and the main channel will transport the net sediment

to the floodplain. Such net sediment transport volume

is the same order of magnitude as that in the water

body of floodplain. Meanwhile, with the increase of

sediment inflow, the net sediment transport from the

main channel to the floodplain gradually increases. It

can be seen that in the lotus-root-shape compound

channels, part of the sediment in water body of main

channel will be transported to the floodplain, and the

sediment concentration of the main channel itself will

also decrease, which is reflected in the ratio of

average sediment concentration of the floodplain to

that of the cross section, i.e., the ratio of the average

sediment concentration of the floodplain to that of the

cross section increases as the sediment inflow

increases. The ratio of the average sediment

concentration of the main channel to that of the cross

section decreases as the sediment inflow increases.

Before the sediment in the water body of floodplain

is saturated, the average sediment concentration of

the floodplain and that of the cross section vary

greatly. After the sediment in the water body of

floodplain reaches saturation, the sediment in the

water body of floodplain will become silted. As the

sediment inflow increases, the siltation on the

floodplain gradually increases, which further

suppresses the increase in the average sediment

WRE 2021 - The International Conference on Water Resource and Environment

176

concentration of the main channel and the cross

section, resulting in a decrease in the ratio of the

average sediment concentration of the floodplain to

that of cross section.

Figure 6 shows the relationship between the

relative sediment concentration of the straight

channel and the lotus-root-shape channel, the relative

water depth and the relative flow velocity of

floodplain. It can be seen from the figure that the

average sediment concentration ratios of the straight

channel and the lotus-root-shape channel both

increase with the increase in the relative water depth

of floodplain. However, the average sediment

concentration ratio of the floodplain along straight

channel increases faster with the relative water depth

of the floodplain, while the width of the lotus-root-

shape channel increases relatively slowly; the average

sediment concentration ratio of the floodplain of

straight channel and lotus-root-shape channel

increases with the rise in relative flow velocity of the

floodplain, while the amplitudes of the two channels

vary little with the relative flow velocity of the

floodplain.

Figure 6: Relations among relative velocity, sediment

concentration and depth for floodplain and main channel.

4.2 Distribution of Vertical Sediment

Concentration

It can be seen from Table 1 that the vertical gradient

of the sediment concentration of the lotus-root-shape

compound channels is smaller than that of the straight

compound channels. For the same river type,

regardless of the straight channels or lotus-root-shape

channels, the vertical average gradient of the average

sediment concentration of floodplain is always

significantly greater than that of the average sediment

concentration of the main channel, and that of

sediment concentration gradually increases from the

vicinity of floodplain interface to both sides of the

floodplain. It is shown that the vertical unevenness of

the sediment concentration of the floodplain is rather

larger than that of the main channel. Near the

interface of the floodplain, this unevenness reaches a

minimum value and gradually increases toward both

sides.

Table 1: Transverse gradient changes of vertical average

sediment concentration (kg/ m3.m).

Transverse

distance

(m)

0.00 0.08 0.12 0.15 0.25 0.35 0.45

Straight

channel

22.12 19.79 19.42 70.08 96.15 100.65 121.81

Louts-root-

shape

channel

16.47 15.86 15.62 64.13 77.34 80.51 99.21

Ddifference

etween the

two

5.66 3.93 3.80 5.95 18.82 20.14 22.61

5 CONCLUSION

By comparing the flow capacity of three types of

channels, i.e., single channel, straight compound

channel and lotus-root-shape compound channel, it is

known that the single channel has the largest flow

capacity, followed by the straight channel, and that of

the lotus-root-shape channel is the smallest.

The velocity ratio and discharge ratio of straight

channel and lotus-root-shape channel increase with

the increase of the relative water depth of plain and

channel, and the ratio of lotus-root-shape channel is

greater than that of straight channel.

The distribution of sediment concentration in the

floodplain of the lotus-root-shape compound channel

is similar to that of the straight compound channel.

However, the sediment concentration ratios of

Flow and Sediment Movement Characteristics on the Varisized Plain of Compound Channel

177

floodplain cross section of the two types show

contrary change laws with sediment inflow.

ACKNOWLEDGEMENTS

This research was supported was supported by

National Key Research and Development Program of

China (grant No. 2018YFC0407305) and the

National natural science foundation of China (grant

No. 51879282) and Technology Project of Power

China (grant No. DJ-PTZX-2019-05)).

REFERENCES

Armugha, K., Liaqat, A. K. R., Ali, P. Y., & Himanshu, G.

(2018). Characterization of channel planform features

and sinuosity indices in parts of Yamuna River flood

plain using remote sensing and GIS techniques.

Arabian Journal of Geosciences. 11(17), 1-11.

Chen, L., & Zhan, Y. Z. (1996). The form and function of

water and sediment exchange in overbank and high

sand - bearing stream. Journal of Sediment Research. 2,

45-9.

Hu, C. H., Ji, Z. W., & Guo, Q. C. (2010). Flow movement

and sediment transport in compound channels. Journal

of Hydraulic Research, 48(1), 23-32.

Ji, Z. W., Hu, C. H., & Ji, M. D. (2016). Distribution

characteristics of sediment grain size in compound

channel. Journal of Basic Science and Engineering,

24(4), 649-60.

Ji, Z. W., Hu, C. H., & Zhao, X. (2019). Characteristics of

water and sediment distribution in the lotus-root-shape

compound channels. Proceedings of the 38TH IAHR

World Congress-IAHR (pp. 307-314). Panama.

Knight, D. W. (1999). Flow mechanisms and sediment

transport in compound channel. Sino-US Workshop on

Sediment Transport and Disasters, 14(2), 217- 36.

Knight, D. (2005). Sediment transport in rivers with

overbank flow. Journal of Siehuan University

(Engineering Science Edition). 37, 16-29.

Lyhess, J. F., Myers, W. R. C., Cassells, J. B. C., &

Sullivan, J. J. (2001). Influence of planform on flow

resistance in mobile bed compound channels.

Proceedings of 11w Institution of Civil EngiBeers

(Water Maritime and Energy), 148(1), 5-14.

Moron, S., Edmonds, D. A., & Amos, K. (2017). The role

of floodplain width and alluvial bar growth as a

precursor for the formation of anabranching rivers.

Geomorphology, 278(1), 78-90.

Tang, X. N., & Knight, D. W. (2006). Sediment transport

in river models with overbank flows. Journal of

Hydraulic Engineedng, 132(1), 77-86.

Wormleaton, P. R., Sellitl, R. H. J., Bryant, T., Loveless, J.

H., Hey, R. D., & Calmur, S. E. (2004). Flow structures

in a two-stage channel with a mobile bed. Journal of

Hydraulic Research, 42(2), 145-62.

Wu, W. M., Wang, L., Ma, X. D., Nie, R. H., & Liu, X. N.

(2020). Flow Characteristics and Bed Morphology in a

Compound Channel between Two Single Channels.

Water, 12(12), 3544-3544.

WRE 2021 - The International Conference on Water Resource and Environment

178